Temperature dependence of the Kerr effect in a silica optical fibre

The temperature dependence of the electro-optic Kerr effect has been measured in a silica-cored monomode optical fibre. The Kerr constant was measured as 5.3×10?16 mV?2 at 23°C with a temperature coefficient of +0.56% per deg C over the range 23 to 88°C. This measurement has implications for optical-fibre temperature and electric field sensors.     

新型光电式高电压测量器

介绍了应用于高电压计测的光电技术及其工作原理,展示了光电技术在电力系统测量中具有的优越特性．利用电光效应原理及光相位调制方式（调制频率f=50kHz）,研制成Pockcls／Kerr新型光电式高电压测量器,旨在取代体积、质量大,制造成本高的传统式电压互感器,以适应电力系统中信息传输、计量诊断自动化、数字化以及小型轻量化的发展要求．     

Recent progress in integrated electro-optic frequency comb generation

Optical frequency combs have emerged as an important tool enabling diverse applications from test-and-measurement,including spectroscopy,metrology,precision distance measurement,sensing,as well as optical and microwave waveform synthesis,signal processing,and communications.Several techniques exist to generate optical frequency combs,such as mode-locked lasers,Kerr micro-resonators,and electro-optic modulation.Important characteristics of optical frequency combs include the number of comb lines,their spacing,spectral shape and/or flatness,and intensity noise.While mode-locked lasers and Kerr micro-resonators can be used to obtain a large number of comb lines compared to electro-optic modulation,the latter provides increased flexibility in tuning the comb spacing.For some applications in optical communications and microwave photonics,a high degree of integration may be more desirable over a very large number of comb lines.In this paper,we review recent progress on integrated electro-optic frequency comb generators,including those based on indium phosphide,lithium niobate,and silicon photonics.     

Quadratic Electro-Optic Kerr Effect: Applications to Photonic Devices

We propose novel applications of the quadratic electro-optic Kerr effect to photonic devices. Specifically in this work, two new illustrative examples are described, namely an electrically controlled multistable switch (ECMS), and an electrically tunable Bragg grating (ETBG). Their functionality is based on the third-order nonlinearity in an isotropic medium. On one hand, we note that the first key feature is the all-optical as well as electro-optical control/tunability. This can be achieved only in the third-order nonlinear material as opposed to a more frequently used linear electro-optic effect exploited in optical crystals. On the other hand, the second important key feature is the availability of integrated and compatible materials that show third order nonlinearity. In the first application proposed here, ECMS, the interplay between the quadratic electro-optic and all-optical Kerr effects is crucial for its tunable operation and leads to an interesting feature of storing an electrical information optically. In the second example, ETBG, employing the quadratic electro-optic effect makes it attractive thanks to the existence of the third-order nonlinearity in many interesting isotropic materials that are suitable for device integration. Devices such as modulators, switches, mixers, variable attenuators or optical limiters can be designed.     

新型软光电材料-离子液体电光调制特性

采用实验方法研究了新型软光电材料离子液体的电光调制特性。研究表明外加低频交流电信号时, 光功率输出与电信号相同频率振荡, 振幅受调制信号幅度和频率的共同影响, 电压幅度越大, 电压频率越低, 光输出振荡幅度越大; 外加直流电信号时, 光功率输出呈光开关状态。对影响光功率变化的因素, 如离子液体种类、调制部分物理尺寸以及离子液体折射率、电导率等进行了研究分析, 并对实验现象进行初步解释。     

Measurement of Frequency Shift Characteristics Based on LiNbO3 Waveguide Electro-Optic Intensity Modulator

High-speed and wide-band LiNbO3 waveguide electro-optic intensity modulator has drawn great attention in the field of optical fiber communication and sensor. This paper reports the research results on the measurement of frequency shift characteristics of Mach-Zehnder electro-optic intensity modulator. Two measurement methods of frequency shift characteristics for high and low frequency modulations are studied in theory and experiment and demonstrate different results. The realization of a multi-wavelength optical source based on Mach-Zehnder electro-optic intensity modulator has been introduced. The technique to reach the maximum intensity for interesting shift frequency, particularly for heterodyne detection of Brillouin distributed optical fiber sensing, has been given.     

Measurement of Frequency Shift Characteristics Based on LiNbO_3 Waveguide Electro-Optic Intensity Modulator

High-speed and wide-band LiNbO3 waveguide electro-optic intensity modulator has drawn great attention in the field of optical fiber communication and sensor. This paper reports the research results on the measurement of frequency shift characteristics of Mach-Zehnder electro-optic intensity modulator. Two measurement methods of frequency shift characteristics for high and low frequency modulations are studied in theory and experiment and demonstrate different results. The realization of a multi-wavelength optical source based on Mach-Zehnder electro-optic intensity modulator has been introduced. The technique to reach the maximum intensity for interesting shift frequency, particularly for heterodyne detection of Brillouin distributed optical fiber sensing, has been given.     

Measurement of quadratic electro-optic effect in polydiacetylene optical waveguide

Planar optical waveguides of the soluble polydiacetylene 9-SMBU were formed by dip-coating on silicon substrates. The quadratic electro-optic (Kerr) response was measured by guided wave polarisation interferometry. The effective electro-optic coefficient was found to be 3.7*10/sup -20/ m/sup 2/V/sup -2/ at a wavelength of 1.3 mu m.<>     

BSO/fibre-optic voltmeter with excellent temperature stability

A new BSO/fibre-optic voltmeter for measurement of AC voltage from 0 to 500 V has been successfully developed for practical use in various fields. This voltmeter has been given outstanding temperature stability of within ± 0.2% from ?10°C to 85°C by using the electro-optic effect of a 4.7 mm-thick Bi12SiO20.     

旋转波片法在低应力测量中的应用

本文提出用旋转λ/2波片和分析片来代替转动物体的新方法,解决了用电光调制法测定某些物体低应力值时,物体很难转动的难题.     

Novel technique for investigating high-power microwave pulses using Kerr effect

A novel method for the measurement of peak power of microwave pulses up to the few hundred kilowatts level based on the microwave-induced electro-optical Kerr effect in nonlossy dielectric liquids is described. This method provides additional information about the shape of the pulse, which is not usually given by the conventional methods.<>     

激光多普勒移频特性研究

为了提高激光多普勒测速系统的性能,增强系统与应用场景适配性,文中对比电光和声光两种主要移频器件的特点,从器件移频原理出发,提出了简化频率变换关系的分析方法,从理论上研究激光多普勒测速系统中两种器件产生的移频特性,搭建铌酸锂电光调制和声光移频全光纤激光测速系统链路,将测试频率特征与理论特征进行对比研究,提出一种新型声电混合调制激光多普勒测速系统。结果表明,该新型系统兼具声光移频测速系统可测量运动目标运动方向、运动速度,完成电光调制测速系统多频率校正的特点,频率测量相对误差较小,动态范围大。通过研究两种移频方式对频率特性,为设计高性能激光多普勒测速系统提供了理论和实验支撑。     

Loss Measurements on Polymer Thin Film Optical Waveguides

Asimple setup for the measurement of transmission loss in polymer thin film optical waveguides is described.A new electro-optic polymer film has been prepared.The transmission loss of the film is measured before and after corona poling.And the loss is determined to be 1.84 dB/cm and 2.14dB/cm, respectively.     

硅酸镓镧晶体电光调制器

用新型非线性材料硅酸镓镧(LGS)晶体制作了电光调制器,研究了单晶硅酸镓镧晶体的电光效应。利用极值法和倍频法测定了硅酸镓镧晶体的半波电压值,计算出电光系数γ11分别为1.85pm/V和1.90pm/V,对比发现倍频法比极值法实用、快速、方便。测定了在0.3～0.6328μm波长内硅酸镓镧单晶的旋光率为21.1°～2.6°/mm。利用自制的高压调制电源进行了调制实验,实验结果表明:有旋光性非线性材料硅酸镓镧晶体是一种新型电光晶体,可用作电光调制器,调制信号稳定。     

Measurement of spatio-temporal terahertz field distribution byusing chirped pulse technology

The authors report the use of an optoelectronic system for the measurement of terahertz (THz) pulses by using chirped pulse technology. This system measures the spatio-temporal distribution of free-space pulsed radiation with an unprecedented data acquisition-rate. Using a linearly chirped optical probe pulse with an electro-optic crystal, a temporal waveform of a copropagating THz field is linearly encoded onto the frequency spectrum of the optical probe pulse and then decoded by dispersing the probe beam from a grating to a detector array. Acquisition of picosecond THz field pulses without using mechanical time-delay devices have been achieved. A single-shot electro-optic measurement of the temporal waveform of a THz pulse has been demonstrated. Unparalleled by other THz sampling techniques, this single-shot method provides what is believed to be the highest possible data-acquisition rate. Temporal resolution, sensitivity, optimal optical bias point of electro-optic modulation, potential applications, and possible improvements are also discussed. In principle, this technique can also be used in magneto-optic measurements     

Millimetre-wave active probe frequency-multiplier for on-wafer characterisation of GaAs devices and ICs

A millimetre-wave active probe quintupler with an output frequency range of 60 to 100 GHz has been developed. The frequency multiplier circuit was implemented in a coplanar waveguide. Using this probe along with the electro-optic sampling technique, on-wafer millimetre-wave vector measurement up to 100 GHz and time-waveform measurement at 77 GHz of test structures on a GaAs substrate have been demonstrated.<>     

Picosecond electro-optic probing of high-speed integrated circuits using external GaAs tip

External electro-optic sampling has been demonstrated on high-speed integrated circuits using a pulse-compressed mode-locked Nd:YAG laser and a sophisticated GaAs probe tip. The measurement at frequencies up to 40 GHz has been successfully performed with excellent voltage sensitivity of less than 3 mV/ square root (Hz).<>     

基于微波光子的射频信号功率测试方法

功率是微波信号的基本参数之一。传统的功率测量方法受限于同轴电缆传输损耗大、体积大等因素，难以适应分布式长距离组网应用。文章提出基于电光转换的微波功率测量方法，将微波功率测量转换为对光边带抑制比的测量。分别分析了采用相位调制和强度调制的电光转换方法时，微波功率与光边带抑制比之间的映射关系。实测对比了测量值与理论计算值之间的符合性。该方法经过电光转换后，可以采用光纤传输信号，进行长距离远拉测试，在分布式长距离组网中具有较好的应用前景。     

基于PXI的光电瞄准设备自动检测系统

光电瞄准自动检测系统是在PXI测试总线技术的基础上,有机地结合计算机技术和虚拟仪器测量技术,研制开发出的新一代检测系统。检测系统采用了PXI总线技术和规范的系统结构框架,通过选取NI公司的PXI-1010混合机箱、PXI-8187主控制器、SCXI-1130矩阵开关、SCXI-1167继电器驱动模块、PXI-6509数字I／O、PXI-6229数据采集、PXI-4070数字万用表、PXI-5122数字化仪功能模块以及EXC公司的DAS-429cPCI／Mx、Condor公司基于cPCI的MIL-STD-1553和DDC公司的SB．36200IX模块,并利用LabVIEW开发工具开发出检测系统,而且还解决了PXI模块硬件及驱动程序与被测产品匹配问题,实现了基于PXI虚拟仪器的软面板技术。该检测系统是根椐标准的数据采集——信号分析与处理——输出及显示的结构模型而建立的,实现了光电瞄准系统数据的实时采集、处理和显示。光电瞄准自动检测系统样机实现了产品的自动化检测,具有一定的技术先进性。     

OPSEF: an optical sensor for measurement of high electric field intensity

An optical sensor for measurement of high electric field intensity by means of the electro-optic effect in single-crystal bismuth silicon oxide has been successfully developed and the fundamental characteristics measured. By use of this sensor, the electric field intensities between parallel and coaxial electrodes have been measured.